Outdoor lamps of the prior art usually have a special lampshade designed according to various needs. To control light pollution, the unnecessary light extension that causes an uncomfortable visual effect, an outdoor is usually provide a fixed lampshade.
According to the research data, light pollution has been causing serious eye damage to people. When people choose outdoor lighting devices, the main consideration is the ornamental effect. Therefore, the illumination range and strength may go beyond a reasonable level, which not only damages people's vision but also disturbs brain functions, resulting in vertigo, sleeplessness, distraction and poor appetite. Light pollution causes even larger damages to children, since their visual ability are still developing. Therefore, effective control of light pollution is important.
Although the lampshades of the outdoor lamps of the prior art can restrict the projection range of the lamps, the projection range is however fixed and cannot satisfy the necessity of adopting different ranges in different occasions.